A HDD disk (or platter) is the magnetic storage medium on which data is stored on the HDD. User-accessible information is magnetically recorded on the magnetic surface of a HDD disk in disk sectors, the smallest size of controllable data in a HDD. Defects or defect patterns may arise on the surface of the disk as it is processed and handled by a plurality of processing stations during manufacture of the disk For example, disk defects can be water stains caused by water in the groove in an insufficiently dried cassette. The stain can be caused by any one of the grooves of the cassette.
Quickly determining the processing station or stations responsible for disk defects is desirable, particularly during yield crisis periods. Current methods of identifying the source (processing station) of disk defects can be time-consuming and not easily adaptable to the different processing stations. For example, in one existing process for detecting whether sputter pins cause defects in a disk, the disk needs to be rescanned using an Optical Surface Analyzer (OSA) to identify the sputter pin location. The OSA scan can then be compared with an existing map of the disk's defects to determine if the sputter pins caused defects on the disk's surface. This existing process may take over an hour and is only adapted to detect sputter pin defects.